The effective DEM 133 /nt isn't too bad (quite good if it includes breakfast). I paid slightly more (DEM 173) in August. My only complaint about the room was that the a/c was barely adequate (not something to worry about now?) otherwise it was quite nice.
As for location, it all depends on what you want. It's right across from one of the concert halls and not too far from the opera house. I think the Guggenheim(?) is close by too. There is a little neighborhood across the canal (associated with the local church) that supposedly replicates the atmosphere of pre-war medieval Berlin.
See:
http://www.flyertalk.com/forum/Forum81/HTML/001142.html
[This message has been edited by terenz (edited 02-08-2001).]